App Nap is a brand-new feature of Mavericks that reduces resources for apps in the background, in hopes that they will reduce power consumption. However, some apps may behave poorly with this new feature. If you notice erratic behavior from your backgrounded apps, you can turn off App Nap on a per-app basis by opening the Get Info panel for an app in your Applications folder. Here, uncheck the box labeled “Prevent App Nap.”
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